feat: add comments functionality and integrate Socket.io for real-time updates

- Implemented a full comments module in the backend with repository, service, controller, and DTOs using NestJS.
- Added frontend support for comments with a `CommentSection` component and integration into content pages.
- Introduced `SocketProvider` on the frontend and integrated Socket.io for real-time communication.
- Updated dependencies and configurations for Socket.io and WebSockets support.

backend/src/comments/repositories/comments.repository.ts

@@ -0,0 +1,53 @@
+import { Injectable } from "@nestjs/common";
+import { and, desc, eq, isNull } from "drizzle-orm";
+import { DatabaseService } from "../../database/database.service";
+import { comments, users } from "../../database/schemas";
+import type { NewCommentInDb } from "../../database/schemas/comments";
+
+@Injectable()
+export class CommentsRepository {
+	constructor(private readonly databaseService: DatabaseService) {}
+
+	async create(data: NewCommentInDb) {
+		const [comment] = await this.databaseService.db
+			.insert(comments)
+			.values(data)
+			.returning();
+		return comment;
+	}
+
+	async findAllByContentId(contentId: string) {
+		return this.databaseService.db
+			.select({
+				id: comments.id,
+				text: comments.text,
+				createdAt: comments.createdAt,
+				updatedAt: comments.updatedAt,
+				user: {
+					uuid: users.uuid,
+					username: users.username,
+					displayName: users.displayName,
+					avatarUrl: users.avatarUrl,
+				},
+			})
+			.from(comments)
+			.innerJoin(users, eq(comments.userId, users.uuid))
+			.where(and(eq(comments.contentId, contentId), isNull(comments.deletedAt)))
+			.orderBy(desc(comments.createdAt));
+	}
+
+	async findOne(id: string) {
+		const [comment] = await this.databaseService.db
+			.select()
+			.from(comments)
+			.where(and(eq(comments.id, id), isNull(comments.deletedAt)));
+		return comment;
+	}
+
+	async delete(id: string) {
+		await this.databaseService.db
+			.update(comments)
+			.set({ deletedAt: new Date() })
+			.where(eq(comments.id, id));
+	}
+}